Structural and biochemical characteristics of arterial stiffness in patients with atherosclerosis and in healthy subjects

Evaluation of aortic stiffness by echocardiography in tympanosclerosis patients

BACKGROUND AND AIMS

Tympanosclerosis (TS) is a scarring process that may occur during otitis media. Aortic stiffness (AS) is a significant predictor for the development of heart diseases due to its close relationship with atherosclerosis. Similar pathophysiological processes based on inflammation may explain both TS and AS formation. This study aimed to determine echocardiographically whether aortic elasticity is impaired in TS-detected patients and to correlate blood inflammatory parameters with TS and aortic elasticity.

METHODS

Ninety-eight participants diagnosed with chronic otitis media were enrolled in the study. TS-detected 42 participants were assigned to the study group, while 56 without TS constituted the control group. The two groups' demographic, clinical, echocardiographic, and laboratory characteristics were comparable.

RESULTS

Demographic, clinical, and laboratory parameter differences were insignificant. Hs-CRP, neutrophil-to-lymphocyte ratio, and systemic immune-inflammation index were significantly higher in the study group than in the control group (P=0.018, P=0.003, P=0.019, respectively). The study group had significantly lower aortic strain (11.80 ± 4.84 vs. 16.30 ± 3.91; P<0.001) and distensibility (5.23 ± 2.68 vs. 7.24 ± 2.89; P=0.001) values than the control group. The AS index was significantly higher in the study group than in the control group (4.81 ± 2.41 vs. 3.12 ± 1.02; P<0.001).

CONCLUSION

In TS-detected patients, AS parameters were found to be impaired. Aortic elasticity parameters measured by echocardiography, a non-invasive and easily accessible method, may signify early cardiovascular involvement in TS-developed patients.

Serum Malondialdehyde-Oxidized Low-Density Lipoprotein Level Is Associated with Arterial Stiffness by Cardio-Ankle Vascular Index in Coronary Artery Bypass Graft Patients

A high malondialdehyde-oxidized low-density lipoprotein (MDA-oxLDL) level is associated with atherosclerotic cardiovascular diseases and major adverse cardiovascular events. A higher cardio-ankle vascular index (CAVI) is independently associated with an increased risk of cardiovascular events, cardiovascular mortality, myocardial infarction, and stroke in patients with cardiovascular risk. Thus, this study aimed to evaluate the relationship between serum MDA-oxLDL levels and CAVI in patients with triple-vessel coronary artery disease who underwent coronary artery bypass graft (CABG) surgery. Fasting blood samples and baseline characteristics were obtained from 88 patients who had undergone CABG. A commercialized enzyme-linked immunosorbent assay was used to measure MDA-oxLDL levels. An automatic pulse wave analyzer was used to measure CAVI values, and each side of CAVI values of ≥9 was designated as arterial stiffness. In total, 47 participants were assigned to the arterial stiffness group. More patients had diabetes mellitus, were older, and had higher serum MDA-oxLDL levels in the arterial stiffness group than in the control group. A multivariate logistic regression analysis disclosed that MDA-oxLDL and diabetes mellitus were independent predictors of arterial stiffness. Moreover, according to the Spearman's correlation analysis, the serum MDA-oxLDL level was positively associated with both left and right CAVI. Serum MDA-oxLDL levels were positively associated with arterial stiffness in patients who had undergone CABG.

Aging of the Arterial System

Aging of the vascular system is associated with deep changes of the structural proprieties of the arterial wall. Arterial hypertension, diabetes mellitus, and chronic kidney disease are the major determinants for the loss of elasticity and reduced compliance of vascular wall. Arterial stiffness is a key parameter for assessing the elasticity of the arterial wall and can be easily evaluated with non-invasive methods, such as pulse wave velocity. Early assessment of vessel stiffness is critical because its alteration can precede clinical manifestation of cardiovascular disease. Although there is no specific pharmacological target for arterial stiffness, the treatment of its risk factors helps to improve the elasticity of the arterial wall.

A Retrospective Cohort Study of the Association between Serum Osteopontin Levels and Aortic Stiffness in Hypertensive Patients

By suppressing mineralization and preventing ectopic calcium deposits, osteopontin (OPN) has an inhibitory effect on vascular calcification. Also, there is an association between OPN and aortic stiffness (AS). We aimed to investigate the association between serum OPN levels and AS measured by carotid–femoral pulse wave velocity (cfPWV) in hypertensive patients. Baseline characteristics and fasting blood sampling of 120 participants with hypertension and 120 participants without hypertension were acquired. Serum OPN concentrations were determined by enzyme-linked immunosorbent assay. In total, 43 (35.9%) participants were assigned to the AS group with cfPWV of >10 m/s in hypertensive patients. There were more patients with diabetes mellitus, old age, high systolic blood pressure, high serum intact parathyroid hormone (iPTH), elevated C-reactive protein, and high OPN levels in the AS group compared with the control group in hypertensive participants. A multivariate logistic regression analysis discloses that age, SBP, serum OPN, and iPTH levels were independently associated with AS in hypertensive patients. Moreover, according to a multivariate forward stepwise linear regression analysis, OPN level is positively associated with cfPWV. In conclusion, serum OPN level is assumed to be a potential biomarker to predict AS and is positively associated with cfPWV in patients with hypertension.

Vascular Stiffness in Aging and Disease

The goal of this review is to provide further understanding of increased vascular stiffness with aging, and how it contributes to the adverse effects of major human diseases. Differences in stiffness down the aortic tree are discussed, a topic requiring further research, because most prior work only examined one location in the aorta. It is also important to understand the divergent effects of increased aortic stiffness between males and females, principally due to the protective role of female sex hormones prior to menopause. Another goal is to review human and non-human primate data and contrast them with data in rodents. This is particularly important for understanding sex differences in vascular stiffness with aging as well as the changes in vascular stiffness before and after menopause in females, as this is controversial. This area of research necessitates studies in humans and non-human primates, since rodents do not go through menopause. The most important mechanism studied as a cause of age-related increases in vascular stiffness is an alteration in the vascular extracellular matrix resulting from an increase in collagen and decrease in elastin. However, there are other mechanisms mediating increased vascular stiffness, such as collagen and elastin disarray, calcium deposition, endothelial dysfunction, and the number of vascular smooth muscle cells (VSMCs). Populations with increased longevity, who live in areas called “Blue Zones,” are also discussed as they provide additional insights into mechanisms that protect against age-related increases in vascular stiffness. Such increases in vascular stiffness are important in mediating the adverse effects of major cardiovascular diseases, including atherosclerosis, hypertension and diabetes, but require further research into their mechanisms and treatment.

Influence of the order of aerobic and resistance exercise on hemodynamic responses and arterial stiffness in young normotensive individuals

AIMS

To investigate the effects of a combination of aerobic and resistance exercises and the inverse sequence on the hemodynamic parameters and indicators of arterial stiffness in healthy young adult subjects.

METHODS

Fifteen subjects were randomized in a crossover procedure according to two experimental conditions: combined aerobic exercise (30 min of treadmill running, 75-80% - peak VO₂) followed by resistance exercise (5 exercises, 3 sets - 10 RM) (AR) or vice versa (RA). Data of the hemodynamic parameters and arterial stiffness were obtained at baseline and after exercise (post-10, post-20, and post-30 min). Two-way ANOVA for repeated measurements was performed with the Newman-Keuls post-hoc. The significance level adopted was p < 0.05.

RESULTS

The results of the two-way ANOVA for repeated measures were not statistically significant for brachial and central systolic and diastolic blood pressure, respectively, or arterial stiffness indicators: reflected wave indicators and pulse wave velocity (P > 0.05). Statistically significant interactions were observed before and after the exercise sessions for heart rate and rate pressure product (P = < 0.001).

CONCLUSION

The performance order of aerobic exercise followed by resistance exercise (AR) and the reverse order (RA) present similar changes in blood pressure (BP) and arterial stiffness. However, resistance exercise before aerobic exercise promotes increases in heart rate and rate product pressure.

Factors Associated to Arterial Stiffness in Patients With Symptomatic Peripheral Artery Disease

BACKGROUND

The aim of this study was to identify the clinical factors associated with arterial stiffness in patients with symptomatic peripheral artery disease.

METHODS

In this cross-sectional study, 181 patients (67% men; mean aged 66 ± 9 years) were recruited and had their central arterial stiffness assessed by carotid-femoral pulse wave velocity (cf-PWV). Clinical characteristics are sociodemographic data, body mass index, comorbid conditions, and walking capacity.

RESULTS

Multiple linear regression analysis showed that age (b = 0.182, P = 0.032), body mass index (b = 0.254, P = 0.002), and mean blood pressure (b = 0.249, P = 0.021) were positively associated with cf-PWV.

CONCLUSIONS

Our results showed that the aging, elevated body mass index, and higher blood pressure are clinical factors associated with increased arterial stiffness in patients with peripheral artery disease.

AORTIC POST-RESISTANCE EXERCISE HYPOTENSION IN PATIENTS WITH PERIPHERAL ARTERY DISEASE

ABSTRACT Introduction: A single session of resistance training decreases brachial blood pressure (BP) in patients with peripheral artery disease (PAD). However, it is not known whether similar responses occur in aortic BP, which is a better predictor of cardiovascular risk. Objective: This study aimed to analyze the effects of a single session of resistance training on aortic BP in PAD patients. Methods: This randomized, crossover, controlled trial involved 16 patients. All of them performed a session of resistance training (R - 3 x 10 reps in eight exercises, 5-7 on the OMNI Scale) and a control session (C - resting for 50 min). Before and after each session, aortic BP was assessed by applanation tonometry technique. Results: There was an increase in systolic (P<0.002) and mean (P<0.001) aortic BP in both sessions; however, higher increases were observed in C session (P<0.001). Additionally, diastolic aortic BP only increased after C session (P=0.004). The hypotensive effect of the exercise on systolic, diastolic, and mean aortic BP were -12±2, -6±2, and -7±2 mmHg, respectively. Conclusion: A single session of resistance training promoted a hypotensive effect on aortic BP of patients with PAD, indicating an acute reduction in cardiovascular risk in this population. Level of Evidence I; Therapeutic studies - Investigating the results of treatment.

Metabolomic signature of arterial stiffness in male patients with peripheral arterial disease

Arterial stiffness is an independent determinant of cardiovascular risk and a marker of subclinical organ damage. Metabolomics may facilitate identification of novel low-molecular cardiovascular risk factors. The aim of the present study was to compare metabolic signatures and functional-biochemical characteristics of patients with peripheral arterial disease (PAD) and clinically healthy subjects. We studied 42 men with symptomatic PAD (aged 66±7 years) and 46 healthy men (aged 66±8 years). Aortic pulse wave velocity (aPWV) was assessed by applanation tonometry using the Sphygmocor device. Metabolic profiling was performed with high-performance liquid chromatography and mass spectrometry. Serum oxidized low-density lipoprotein (oxLDL) level was measured by enzyme-linked immunosorbent assay. The aPWV as well as serum levels of lactate, free carnitine and 11 amino acids including tyrosine were higher among the patients with PAD. In contrast, serum levels of pyruvate, citrate, α-ketoglutarate, aconitate and cysteine were higher in the control group. In multiple regression models, aPWV was independently determined by log-tyrosine and log-oxLDL in the patients (R(2)=0.61; P<0.001) and by age, log-pyruvate and log-oxLDL in the controls (R(2)=0.52; P<0.001). Our study describes for the first time significant differences in metabolomic signature of patients with advanced atherosclerosis compared with clinically healthy controls. The aPWV is independently associated with serum levels of tyrosine and oxLDL in the patients with PAD and is related to pyruvate and oxLDL levels in the control group. The measurement of low-molecular metabolites, which are related to changes in vascular phenotypes, may lead to identification of novel vascular risk markers.

LPS induces pro-inflammatory response in mastitis mice and mammary epithelial cells: Possible involvement of NF-κB signaling and OPN

BACKGROUND

Lipopolysaccharide (LPS) has pro-inflammatory properties. This study was conducted to determine whether the LPS induced pro-inflammatory response in a model of mastitis and in mouse mammary epithelial cells (MEC).

METHODS

To investigate the effects of LPS in vivo, 50 μL of a solution of LPS (20 ng/μL) were infused into the mammary glands of mice. To study the effects of LPS in vitro, MEC were exposed to LPS (20 μg/mL) for 24h. Activation of nuclear factor kB (NF-κB) and myeloperoxidase (MPO) were studied. Production of pro-inflammatory cytokines (interleukin-6 [IL-6], tumor necrosis factor-alpha [TNF-alpha], interleukin-1 beta [IL-1 beta]) and expression of osteopontin (OPN) were also evaluated.

RESULTS

After LPS administration, route of NF-κB signaling is activated and the activity of MPO is increased. Furthermore, LPS increases the expression of OPN and production of TNF-alpha, IL-6 and IL-1 beta.

CONCLUSIONS

Present results demonstrate that LPS induces a pro-inflammatory response in a murine model of mastitis and suggest the involvement of the NF-κB pathway and OPN.

Osteopontin - a multi-modal marker and mediator in atherosclerotic vascular disease

Atherosclerosis is a chronic inflammatory process of the vessel wall with systemic correlates. It is now well established that patients' outcome is tightly linked to atherosclerotic plaque stability, potentially more so than to the mere plaque size. Osteopontin (OPN) is an integrin-binding ligand, N-linked glycoprotein, which was recognized as a significant participant in the atherosclerotic inflammatory milieu. Evidence from several genetic mouse models suggests that OPN is an enhancer of atherosclerosis. This may be mediated by its capacity to enhance inflammation in the atherosclerotic plaque. Interestingly, OPN may also possess potentially protective vascular effects, such as attenuation of vascular calcification. In humans circulating levels of OPN were found to be independently associated with the severity of coronary atherosclerosis. Moreover, several studies report that high plasma OPN levels were associated with increased risk for major adverse cardiac events. This review aims to critically assess current understanding of the role of OPN in the atherosclerotic process, from animal models to clinical practice. Specific focus is given to evaluating whether OPN could serve as a marker for monitoring coronary atherosclerosis severity, and in parallel, assess the evidence for its role as a mediator in the pathogenic pathways leading to atherosclerotic vascular disease.

Serum osteopontin level correlates with carotid-femoral pulse wave velocity in geriatric persons

Osteopontin (OPN) is involved in the regulation of vascular calcification processes. The aim of this study was to evaluate the relationship between fasting serum OPN concentration and carotid-femoral pulse wave velocity (cfPWV) in geriatric persons. Fasting blood samples were obtained from 93 geriatric persons. cfPWV were performed by SphygmoCor system. Serum OPN levels were measured using a commercially available enzyme-linked immunosorbent assay. Geriatric adults who had diabetes (P = 0.007) or dyslipidemia (P = 0.029) had higher cfPWV levels than those without diabetes or dyslipidemia. The univariable linear regression analysis showed that age (P = 0.002), waist circumference (P = 0.048), body mass index (P = 0.004), systolic blood pressure (P = 0.001), diastolic blood pressure (P = 0.036), pulse pressure (P = 0.017), creatinine (P = 0.002), and log-OPN level (P = 0.001) were positively correlated with cfPWV levels, while the high-density lipoprotein cholesterol (HDL-cholesterol) level (P = 0.007) and glomerular filtration rate (P = 0.001) were negatively correlated with cfPWV levels among the geriatric adults. Multivariable forward stepwise linear regression analysis of the significant variables also showed that log-OPN (β = 0.233, R (2) = 0.123, regression coefficient: 1.868, P = 0.011) was still an independent predictor of cfPWV levels in geriatric persons.

ABCA1-dependent serum cholesterol efflux capacity inversely correlates with pulse wave velocity in healthy subjects

The capacity of HDL to induce cell cholesterol efflux is considered one of its main antiatherogenic properties. Little is known about the impact of such HDL function on vascular physiology. We investigated the relationship between ABCA1-dependent serum cholesterol efflux capacity (CEC), an HDL functionality indicator, and pulse wave velocity (PWV), an indicator of arterial stiffness. Serum of 167 healthy subjects was used to conduct CEC measurement, and carotid-femoral PWV was measured with a high-fidelity tonometer. J774 macrophages, labeled with [(3)H]cholesterol and stimulated to express ABCA1, were exposed to sera; the difference between cholesterol efflux from stimulated and unstimulated cells provided specific ABCA1-mediated CEC. PWV is inversely correlated with ABCA1-dependent CEC (r = -0.183; P = 0.018). Moreover, controlling for age, sex, body mass index, mean arterial pressure, serum LDL, HDL-cholesterol, and fasting plasma glucose, PWV displays a significant negative regression on ABCA1-dependent CEC (β = -0.204; 95% confidence interval, -0.371 to -0.037). The finding that ABCA1-dependent CEC, but not serum HDL cholesterol level (r = -0.002; P = 0.985), is a significant predictor of PWV in healthy subjects points to the relevance of HDL function in vascular physiology and arterial stiffness prevention.